A conventional sensor apparatus of this kind is described with reference to a drawing. FIG. 3 is an electric circuit diagram showing a conventional sensor apparatus.
As shown in FIG. 3, the sensor apparatus includes: first and second drive circuit sections 1A, 1B each for outputting a drive signal that drives detection device 2; and first and second detection circuit sections 3A, 3B each for fetching a response signals from detection device 2. The sensor apparatus further includes: first and second process circuit sections 4A, 4B, into which response signals from first and second detection circuit section 3A, 3B are inputted and each of which divides the response signal into a monitor signal and a sense signal; and first and second output circuit sections 5A, 5B for outputting sense signals, divided by first and second process circuit sections 4A, 4B, from output terminals 7A, 7B.
The apparatus has been configured such that failure diagnosis circuit 6 targets for failure diagnosis at least one of first and second drive circuit sections 1A, 1B, detection device 2, first and second detection circuit sections 3A, 3B, and first and second process circuit sections 4A, 4B, and in the case of detecting failure, failure diagnosis circuit 6 outputs a failure detection signal from output terminal 8 provided therein. Hereinafter, an object for failure diagnosis is also referred to as a failure diagnosis object section.
It is to be noted that as related art document information concerning this application, for example, Unexamined Japanese Patent Publication No. H08-327363 (Patent Document 1) is known.
Such a conventional sensor apparatus has had a problem of having difficulties in reducing its size.
Specifically, in the above conventional configuration, output terminals 7A, 7B included in first and second output circuit sections 5A, 5B and output terminal 8 included in failure diagnosis circuit 6 are present, and with such a large number of terminals, the reduction in size has been difficult.